ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 malignancy. A high index of suspicion is needed based on the rec- ognition of characteristic histological features, to pursue fungal, mycobacterial, and bacterial organisms - especially gram-positive bacilli - within lipid vacuoles by using ancillary studies, such as Gram stains, and microbiological studies. E-PS-02-033 The impact of increased p53 expression on the clinical out- come in hormone receptor positive breast cancer: a new useful biomarker? M. Üner, H.G. Terzioglu*, K. Kösemehmetoglu, S. Aksoy, A. Üner *Hacettepe University, Turkey Background & objectives: Predicting the prognosis of breast cancer depends on interactions of various biological factors, one of which is p53. In this study, we aim to elucidate the relationship between p53 and survival outcomes in oestrogen receptor-positive/HER2-negative breast cancer. Methods: Slides obtained from tissue microarrays constructed using 3-mm cores of breast tumours from 122 patients were stained for p53. All tumours were scored by multiplying the percentage of p53 positive neoplastic cells with the staining intensity (weak:1 moderate: 2 strong: 3) and the final scores were correlated with the clinical follow-up data to predict biological behaviour. Results: The patient demographics were as follows: The mean age: 42 (range 22-92). Clinical stage of the patients: Stage I; 11 (9.2%) Stage II: 53 (43.8%) and Stage III: 58 (47%). All of the patients received hormone receptor directed therapy, additionally 108 patients received chemotherapy. The median follow-up time of the patients was approximately 50 months. The p53 scores ranged between 0 - 285. Twenty-seven of patients (22%) had a score of 0. Patients with a score of 60 or less (n=91) had a significantly better disease free and overall survival compared to the patients with a score higher than 60 (n=31) (p < 0.001). Conclusion: A variety of methods/tests are used to predict prog- nosis in breast cancer. However, in a world-wide perspective, most of them are not easily affordable. In exchange, surrogate markers, such as ki-67 etc., are more widely used for prognosis prediction. The expression of p53, evaluated by immunohistochemistry, could be a potential surrogate marker to predict clinical outcome in oes- trogen receptor-positive/HER2-negative breast cancer. E-PS-02-034 Distant metastases from phyllodes tumours: a retrospective review from a single institution J. Castro*, J. Azevedo, A. Coutada, J. Costa, C. Leal Barbosa, M. Afonso *IPO Porto, Portugal Background & objectives: Phyllodes tumours (PTs) are rare fibroepi- thelial breast neoplasms. Distant metastases occur in about 2%, almost exclusively in malignant PTs (MPTs). We aim to provide an over- view of metastases from PTs with emphasis in achieving an accurate diagnosis. Methods: Retrospective analysis of all patients diagnosed with distant metastases from PTs in our institution between 2010 and 2022. Evaluation of clinicopathologic features of both primary and metastatic tumours, including age at diagnosis, interval between primary and metastatic disease, site of metastasis, morphological features, immunohistochemical profile and interval between metastatic disease and death. Results: From a total of 265 PTs, nine women with distant metas- tases were identified. All had a MPT diagnosis, three after local recurrence of borderline PT. Mean age at metastasis diagnosis was 58 years and mean interval between primary and metastatic dis- ease was 21.5 months (range 6.0-50.9). Sites of distant metastases included lung (5), bone (2) and soft tissues (2). Metastases pre- sented spindle cell (4), mixed (3), epitheliod (1) and pleomorphic (1) morphology. Heterologous elements were identified in two cases. Epithelial component was absent in all. No immunohisto- chemical marker was helpful for differential diagnosis. Six patients died and mean interval between metastatic disease and death was 11.6 months (range 0.9-39.4). Conclusion: Distant metastasis of PTs are extremely rare and pre- clude a dismal outcome. Diagnosis can be challenging given the absence of a specific morphological pattern and useful immunohis- tochemical markers. Morphological comparison between primary and metastatic lesions remains the most reliable tool for an accurate diagnosis. E-PS-02-035 Rare localizations of metastatic lobular carcinoma – twenty years of experience of two institutions P. Hurník*, J. Strakos, J. Palica, D. Ziak, V. Zidlik, R. Ondrussek, P. Vazan, M. Wozniakova, P. Delongova, F. Fakhouri, J. Skarda *Department of Clinical and Molecular Pathology, University Hospital Ostrava and Faculty of Medicine; University of Ostrava, Department of histology and embryology, Faculty of Medicine, Masaryk University Brno, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Brno, Czech Republic Background & objectives: Lymphatic tissues, breast and skin are the sites most likely to cause metastases of lobular breast cancer. This retrospective observational study focuses on the assessment of rare metastases, which are a significant burden in terms of prognosis. Methods: For the period 2000-2020, those metastatic lobular carcinomas that metastasized into uncommon areas were selected from the databases of two medical facilities (University Hospital Ostrava, CGB Laboratory) in Moravian-Silesian region. The work with the databases was preformed in the CGB laboratories during March 2022, followed by a statistical analysis of a total of 485 patients. Results: The average age of the 485 patients, all of whom were women, was 62.5 years, while the median was 63 years. There was no significant age difference between the cohorts of usual and rare metastases. 70 of all metastases (14.4%) were located out of the lymphatic tissue, breast or skin. The most frequent locali- zations were following: stomach (1.65%), peritoneum, liver and bones (all 1.44%), ovaria (1.24%), omentum (0.82%) and fallopian tube (0.62%). Out of the other unique metastatic localizations can be mentioned for instance cerebellum, orbit, bronchus or adrenal gland. Conclusion: Although the majority of lobular carcinomas metas- tasize to the lymphatic system, skin, or breast, nearly every sixth metastatic location is unusual and may adversely affect the condi- tion of patients. As a result, these areas should be considered in ordinary clinical practice. E-PS-02-036 Extracellular matrix analysis in breast cancer. Study of 5 cases M. Mnikhovich, A. Romanov, T. Sotnikova*, T. Bezuglova *Moscow City Clinical Hospital No.23, Russia S200